My monoplane
glider, the Goat, has been soaring in one version or another since
the spring of 2003. The
Goat is technically an ultralight sailplane (under United States
weight rules) with conventional three axis controls, similar to the
Bug4 and the commercial Super Floater. It is designed for slow speed
recreational gliding and training. I hope this glider will be an all
purpose airchair, allowing comfortable open air soaring, good crash
safety, quick assembly, and convenient car top transport.

The Goat is
an airchair, essentially a garden chair with a wing. This
is Goat4 in March of 2007.

Like the Bug
biplanes, the Goat does not foot launch, but is either towed into the
air or else launched by rolling down a hillside. My rolling launches
are usually made at a site shared with hang gliders and paragliders.
This glider has proved to be a worthy soaring aircraft, flying very
much like a hang glider and readily adapting to hang glider
techniques and procedures. The Goat1 has made a cross country flight
of more than sixty miles, reaching an altitude above 13,000 feet.

This is a home built
glider, made with a low level of technology (no welding, no special
machining, no molds or jigs, no spray rig) from readily available
materials (mostly aluminum tubing, steel cable, aircraft bolts and
heat shrink fabric). The Goat is a noncommercial project, with no
product or plans for sale now or later, but I have posted complete
descriptive drawings of the Bug4 and Goat1 through Goat4 on the Web.
These drawings
are freely available for whatever purpose the user may
desire.

Goat1
on the left, Bug2 on the right, are both carried on truck
top hang glider racks.

My idea of an
"airchair" is that it flies like a hang glider or paraglider but with
improved stability, control, comfort, and crash safety. The glider
can be kept at home and transported to the flying site on a simple
car top rack. It can be assembled by one person in about 20 minutes.
With a wing loading about the same as a hang glider, it flies and
soars like a hang glider, making it compatible with many existing
hang glider operations, using rolling launches, ground tows, or
ultralight aerotows.

A careful pilot knows
his glider and checks it out before flight.

A
high flying airchair pilot must be versed in sailplane procedures
such as assembly, ground handling, preflight inspection, three axis
mechanical flight control, emergency procedures, flying regulations,
airspace restrictions, and the effects of wind and
weather.

Coming
down to the Landing Zone, Bug2 is already
there

Goat1 makes
a rolling takeoff from a gravel
hang glider launch ramp

Goat1 in
Flight

The Goat1 made it's first flight on February
1, 2003, and since then has been flying as a weekend soaring glider.
It has proven to be a pleasant and practical glider for slope
launching and local flying. It is easy to tow behind an ultralight
airplane.The struts fold onto the wing for
transport. As of december, 2009, Goat1 has new fabric and removable, folding main struts,and is now called the Red Goat.

The biggest drawback to the Goat1 design has
been the large size and heavy weight of the main wing panel with
regard to loading or unloading it onto a car top rack. I make a point
of carrying each wing panel by myself most of the time, and I find it
stressful. The folded wing half weighs 42 pounds, which is about my
upper limit for something big and bulky that has to be lifted and
carried in the wind. The primary reason for the Goat2 design was to
have a lighter wing panel to reduce the burden of assembly and
loading.

Goat2 is a simpler,
lighter version of Goat1 with almost exactly the same significant
dimensions. In contrast to Goat1, the wing and tail boom are cable
braced (no struts) and a 14" diameter ground roll tire is used
instead of a 16" tire. The elevator control lines now run directly to
the elevator control arms without any push rod mechanisms, and the
removal of the tail plane for storage and transport has been
simplified. The video clips "Airchair Thermalling" and "Landing in a
Small Field" were taken from Goat2.

Goat2 was light and eliminated the bulky
struts, but all those long cables created their own transport and
assembly problems. This led eventually to the creation of Goat4,
which retained the cable braced wing but simplified a lot of the
assembly mechanics.

Goat3 high
in a desert thermal

Goat3 in flight, (May
2006)

Goat3 has a smaller wing than the other
Goats, with a fancier, sailplane style airfoil. The struts are
removed for transport, and the wing does not have folding panels on
the trailing edge. The seat back and shoulder belts are fixed in
place on the nose section and do not require attention during
assembly.

The reduced wing area of Goat3 forces me to fly faster, and the
new airfoil doesn't seem to be producing any dramatic performance
improvement. As it stands, it looks as if the larger wing with the
simpler airfoil (as used by Goat1 & Goat2) may be a suiperior
combination for an airchair. Goat3 probably won't stay up in light
conditions as well as the others, which leaves me ( body weight 155
lbs., an average weight pilot?) wanting the larger wing.

Goat4 (see photo, second from top of page) is essentially a Goat2 wing with Goat3 nose and tail.

Goat Features

The varioius Goats have these
features:

Five or six major separable
parts, the heaviest being the the wing panel at 35 to 42
lbs.

There are no formal values
established for performance, pilot weight, or maximum speeds or
loads, because no rigorous tests have been performed to measure
these values. There is, however, discussion of these factors on
this page and on the

Unfortunately there is no commercially
manufactured glider that can do all of what the Goat does.
Homebuilding is fun, but people who just want to fly gliders should
be able to "buy and fly" instead. Maybe home built airchairs like the
Goats and Bugs will help generate enough interest to allow commercial
production of an airchair someday. Whoever might choose to develop
and sell airchairs would be in a position to set new standards and
make a great contribution to ultralight soaring. I don't yet know of
anyone doing this, nor would I be a part of that effort, but I will
encourage any moves in that direction.

Author in
Goat1

Drogue
Chute Landing

Climbing on
a static line, truck tow

Bug2 and the
Goat1 on the airchair flight line, preparing for truck
tows.